A problem with shot pin assemblies is the flex or “play” between the assembly's ram and housing.
An illustrative embodiment of a locating pin assembly disclosed herein comprises a body that includes a cylinder assembly for moving a ram in a reciprocally-linear manner. An embodiment of the assembly further includes a bearing coupled to the ram configured to engage a bearing wedge to reduce the “play” between the ram and internal components of the assembly. Illustratively, the bearing and bearing wedge reduce or substantially eliminate this “play” preventing axial rotation of the ram.
Another illustrative embodiment of the locating pin assembly comprises a body, a ram, a bearing wedge, and a bearing. The body includes a cavity having a first surface. The ram is partially disposed in the cavity of the body and extends outward therefrom. The ram is also movable with respect to the body between extended and retracted positions. The bearing wedge is located on the first surface of the wedge. The bearing is attached to the ram which engages the bearing wedge to limit axial rotation of the ram.
In the above and other embodiments, the pin locating assembly may further comprise: a second surface in the body that receives a second bearing wedge; a second bearing attached to the ram which engages the second bearing wedge; the second bearing being located on an opposite side of the ram from the bearing; a stop that is attached to the ram that limits the movement of the ram; at least a portion of the stop being made of a resilient material; a second stop attached to the ram opposite the stop; the stop being adjustable relative to the ram; the stop including a key, and the ram a corresponding key slot to receive the key; the ram including a plurality of key slots; a weld-splatter cover positioned around a portion of the ram; a sensor target coupled to the ram and a sensor spaced apart from the sensor target which is movable relative to the sensor; an actuator that moves the ram; the bearing being roller bearing; and the second bearing being a second roller bearing.
In another illustrative embodiment, the ram may include bearings located on opposite sides of the ram oriented generally perpendicular to the longitudinal extent of the ram. Each bearing may engage a bearing wedge so that axial rotation of the ram about its longitudinal extent can be controlled, limited, and/or eliminated regardless whether that rotational force is exerted clockwise or counter-clockwise with respect to the ram's longitudinal extent. In yet another embodiment, the bearing wedge may have an angled surface (such as 15°) that engages a corresponding angled surface on the body to “wedge” the bearing wedge between a roller bearing attached to the ram and the body. In a further embodiment, ram screws can be used to act on the bearing wedge pushing against it to further wedge it between the roller bearing and the body. It is appreciated that a plurality of these roller bearing/wedge bearing assemblies can be employed.
In still another embodiment, the locating pin assembly may be configured to extend at least partially into, and at least partially out of the body using a cylinder assembly that extends and retracts the ram. The amount of extension or retraction of the ram, i.e., its “stroke,” can be assisted via at least one stop member coupled to the ram. In one illustrative embodiment, the ram may include a slot, cavity, or other receptacle that receives a “key” portion of the stop member. It is further contemplated in other embodiments that there may be a plurality of these receptacles on the ram to affect the length of the stroke. The stop member attaches to the ram by fitting into a key or cavity and engaging a fastener. The portion of the ram that receives the stop may be located in a body that includes an impact surface engageable with at least a portion of the stop to limit movement of the ram. In an illustrative embodiment, the stop may be configured to engage the surface to limit the extension of the ram exterior of the body. Additional embodiments may include the stop having a resilient tip, such as a urethane or other resilient material; the ram may include a stop member on axially opposed sides of the ram perpendicular to its longitudinal extent; a shot pin located in the body to limit the retraction portion of the ram's stroke; and a sensor target may be attached to a location on the ram, such as the stop for detection by a sensor assembly. Illustrative embodiments of the body may include side openings that allow access to the bearings and stops. Covers may be included that are removable via fasteners or other suitable means to gain selective access to the aforementioned sections of the ram.
Additional features and advantages of the shot pin or pin locating assembly will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrated embodiment exemplifying the best mode of carrying out the shot pin or pin locating assembly as presently perceived.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates embodiments of the shot pin or pin locating assembly, and such exemplification is not to be construed as limiting the scope of the shot pin or pin locating assembly in any manner.